兔SAH后NF-κB与脑血管内皮细胞凋亡及脑血管痉挛的关系

NF-κB and cerebral vascular endothelial cell apoptosis and cerebral vasospasm in rabbits after subarachnoid hemorrhage

目的:探讨NF-κB在兔SAH后脑血管内皮细胞凋亡和脑血管痉挛的关系。方法:选用健康清洁新西兰白兔40只,采用二次枕大池注血法建立家兔SAH模型。白兔随机分为五组,分别为3 d组,7 d组,14 d组,干预组及对照组,每组8只。干预组为在7 d时间点注血后加入NF-κB的抑制剂PDTC,对照组为空白对照。实验兔在相应时间点分别处死,采用HE染色观察兔基底动脉血管腔直径的改变和管壁厚度的变化、免疫组织化学法观察兔基底动脉血管壁组织病理改变和NF-κB的表达、用末端标记法(TUNEL)分析兔基底动脉内皮细胞凋亡的变化。结果:SAH后第3天基底动脉血管腔已开始狭窄,管壁增厚,第7天达到高峰,之后渐减轻;干预组与SAH 7 d组比较血管壁变化明显缓解(P<0.05);SAH后3 d NF-κB表达增加,7 d表达最为明显,14 d表达稍减少;干预组基底动脉NF-κB表达较SAH 7 d组明显下降(P<0.05);SAH 7 d组基底动脉细胞凋亡指数较正常对照组显著升高(P<0.05);干预组基底动脉细胞凋亡指数较SAH 7 d组明显下降(P<0.05)。结论:NF-κB促进SAH后脑血管内皮细胞凋亡,NF-κB抑制剂PDTC可以通过抑制细胞凋亡缓解CVS。

Objective：To investigate the relationship between NF-κB and apoptosis of cerebral vascular endothelial cell and cerebral vasospasm（CVS） in rabbits after subarachnoid hemorrhage（SAH）.Methods：Forty healthy sterile rabbits of New Zealand species were selected for the model of SAH by double injections of blood into the cisterna magna and randomized into groups of SAH for 3 days,7 days,14 days,intervention and control（n=8 for each）.The intervention group were added with NF-κB inhibitor pyrrolidinedithiocarbamic acid（PDTC） after blood injection at the 7th day,and the control group were blank.Rabbits were sacrificed at different time points and observed concerning the changes of the vessel wall thickness and the basilar artery lumen diameter after HE staining.Immunohistochemical technique was used to detect the pathological changes of basilar artery vessel wall and the expression of the NF-κB,and terminal Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling（TUNEL） was included to analyze the condition of the cell apoptosis of the basilar arteries.Results： Narrowed lumen of basilar artery was seen in rabbits by the 3rd day of SAH,with thickened vessel wall,and the condition peaked at day 7 before gradual subsiding.The vessel wall was alleviated significantly in SAH rabbits at day 7 by intervention of PDTC（P0.05）.The expression of NF-κB was increased by the 3rd day after SAH and prominent at day 7,yet it was down-regulated somewhat at day 14.In the intervention group,the expression of NF-κB was significantly lower than that of 7-day group（P0.05）.Compared with the control group,the apoptotic index for the basilar vessels climbed up in animals by the 7th day of SAH,but dropped significantly in the intervention group.Conclusion：NF-κB appears to cause the apoptosis of vascular endothelial cells,and yet,NF-κB inhibitor PDTC may alleviate cerebral vasospasm through inhibiting apoptosis of endothelial cells.